Position-specific asymmetric deuterium enriched catecholamine derivatives and medicaments comprising said compounds

ABSTRACT

wherein, R1 is deuterium, R2, and R3 are independently selected from hydrogen and deuterium and wherein at least one of R2 and R3 has a deuterium enrichment in the range from 0.02 mol % to 100 mol % deuterium, and wherein the deuterium enrichment of R2 and R3 is different from each other and that the difference between the deuterium enrichment of R2 and R3 is at least 5 percentage points, R4 is hydrogen, deuterium, C1 to C6-alkyl or C5 to C6-cycloalkyl, deuterated C1 to C6-alkyl or C5 to C6-cycloalkyl, or a group that is easily hydrolytically or enzymatically cleavable under physiological conditions, as well as their physiologically acceptable salts and their stereoisomers, enantiomers or diastereomers in optically pure form. The compounds can easily be prepared by mixing deuterated and non-deuterated compounds in a predefined ratio. The compounds show anti-Parkinson effect at lower doses and show lower side effects.

This application is a continuation of U.S. patent application Ser. No.15/678,797, filed Aug. 16, 2017, which is a continuation of U.S. patentapplication Ser. No. 15/402,343, filed Jan. 10, 2017, now U.S. Pat. No.9,763,904, which is a continuation of U.S. patent application Ser. No.14/765,430, filed Aug. 3, 2015, now U.S. Pat. No. 9,567,289, which is aU.S. national stage, filed under 35 U.S.C. § 371, of InternationalPatent Application No. PCT/EP2014/052267, filed Feb. 5, 2014, whichclaims priority to U.S. Provisional Patent Application No. 61/760,738,filed Feb. 5, 2013 and European Patent Application No. 13182708.1, filedSep. 2, 2013. These priority applications are incorporated by referenceherein.

The present invention relates to position-specific asymmetric deuteriumenriched catecholamine derivatives, methods for their production andmedicaments comprising said compounds, as well as their use in thetreatment of Parkinson's disease.

Known representatives of catecholamines, such as L-DOPA (levodopa) aswell as their carboxylic acid esters, are utilized, among other things,for the treatment of Parkinson's disease and restless leg syndrome. Sucha pharmaceutical which contains levodopa is, for example, Dopaflex®.L-DOPA acts on the dopamine concentration in neurons of the brain.Unlike dopamine itself, it can pass through the blood-brain barrier andis converted into dopamine in the brain.

In addition, levodopa is administered in combination with activeadditives in pharmaceuticals. Combinations of levodopa are used withperipheral decarboxylase inhibitors, with inhibitors of the enzymecatechol-O-methyltransferase (COMT), with inhibitors of the enzymemonoamine oxidase (MAO) and with dopamine β-hydroxylase inhibitors.

In this connection, the decarboxylase inhibitors used are, for example:D,L-serine-2-(2,3,4-trihydroxybenzyl) hydrazide (benserazide),(−)-L-α-hydrazino-3,4-dihydroxy-α-methylhydrocinnamic acid (carbidopa),L-serine-2-(2,3,4-trihydroxybenzyl)hydrazide,glycine-2-(2,3,4-trihydroxybenzyl) hydrazide andL-tyrosine-2-(2,3,4-trihydroxybenzyl)hydrazide. Examples of combinationpreparations of levodopa and decarboxylase inhibitors include, amongothers: Madopar® (levodopa and benserazide hydrochloride) as well asNacom® (levodopa and carbidopa).

Examples of COMT inhibitors are entacapone (Comtan®) and cabergoline,and frequently used MAO inhibitors are selegiline hydrochloride,moclobemide and tranylcypromine.

Calcium 5-butyl picolinate and calcium 5-pentyl picolinate are describedas inhibitors for dopamine-β-hydroxylase (DE-A 2 049 115).

Parkinson's disease is a neurodegenerative disease with a slowprogressive course characterized by different symptoms and signs thatmay be present or develop during the progression of disease. Coresymptoms are bradykinesia and at least one of the following: restingtremor, muscular rigidity and postural reflex impairment. Other symptomsthat may occur during the disease progression are autonomicdisturbances, sleep disturbances, disturbances in the sense of smell orsense, of temperature as well as depressive symptoms and cognitivedysfunctions.

The improvement of the impaired dopaminergic neurotransmission byadministration of L-DOPA is the backbone of the current pharmacotherapy.Patients with advanced Parkinson's disease require higher doses ofdopaminergics but this is limited by motor complications, likefluctuations and involuntarily movements (described as levodopa induceddyskinesia, LIDs). Fluctuations might be due to the shorter striatalpersistence (half-life) of dopamine especially in advanced Parkinson'sdisease patients, also referred to as “Parkinson's patients”. A clinicalestablished approach to prolong striatal dopamine persistence is theco-administration of MAO-B inhibitors which block the main metabolicbreakdown route of dopamine. The induction of LIDs is associated in manypatients with higher CNS dopamine levels generated by large L-DOPAdoses. Currently there are different pharmacological means underdevelopment to treat existing LIDs.

α,β,β-D3-L-DOPA exhibited higher longer-lasting striatal dopamine levelsthan L-DOPA. Correspondingly to the increased availability of dopaminein the striatum, α,β,β-D3-L-DOPA showed improved motor activity comparedto L-DOPA in several Parkinson models (Malmlof et al., Exp Neurol, 2008,538-542; Malmlof et al., Exp Neurol, 2010, 225: 408-415). Theequi-effective dose of α,β,β-D3-L-DOPA compared to L-DOPA was about 60%.The observed longer striatal persistence of dopamine allowed theassumption that fluctuations might be reduced as well.

S/S-2-amino-2,3-dideutero-3-(3,4-dihydroxyphenyl)propionic acid(α,β-D2-L-DOPA) andL-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl)propionic acid(α,β,β-D3-L-DOPA) were shown to increase and prolong the output ofstriatal dopamine significantly more than L-DOPA (WO-A 2004/056724 andWO-A 2007/093450).

The highest striatal dopamine concentrations were found afteradministration of α,β-D2-L-DOPA. Those dopamine levels were even higherthan those after the administration of the triple-deuteratedα,β,β-D3-L-DOPA which included the same deuterated positions as thedouble deuterated L-DOPA.

At the equi-effective dose (same striatal dopamine levels and same motoreffect as L-DOPA), α,β,β-D3-L-DOPA caused significant less dyskinesiathan L-DOPA (Malmlof et al., Exp Neurol, 2010, 225: 408-415).

The problem to be solved according to the invention is to improve theactivity of the known α,β,β-D3-L-DOPA.

As used herein and in the context of the present invention the meaningof “deuterated” is extended to partially or completely deuteratedcompounds. “Completely deuterated” compounds are compounds in which atleast 98 mol % deuterium are present in the respective position withinthe chemical compound (The deviation to 100 Mol % is caused byanalytical measurement deviation and experimental errors.) This meansthat there has been achieved an enrichment of deuterium in therespective position and that hydrogen has been replaced. The respectiveenrichment may be performed by chemical reaction in that one usesdeuterated starting materials in chemical reactions or that anhydrogen/deuterium exchange has been performed by mixing respectivecompounds.

“Deuterated” is therefore not related to any naturally occurringdeuterium in hydrogen compounds. As it is known, deuterium is present inhydrogen in natural abundance to an extend of 0.015 mol %. Any abundanceor enrichment that is greater than 0.02 mol % is understood as being“deuterated” in the sense of this present invention.

The problem is solved according to the invention by providing deuteratedcatecholamine derivatives of the general Formula I:

wherein

R₁ is deuterium,

R₂, and R₃ are independently selected from hydrogen and deuterium andwherein at least one of R₂ and R₃ has a deuterium enrichment in therange from 0.02 mol % to 100 mol % deuterium, and

wherein the deuterium enrichment of R₂ and R₃ is different from eachother and that the difference between the deuterium enrichment of R₂ andR₃ is at least 5 percentage points,

R₄ is hydrogen, deuterium, C₁ to C₆-alkyl or C₅ to C₆-cycloalkyl,deuterated C₁ to C₆-alkyl or C₅ to C₆-cycloalkyl, or a group that iseasily hydrolytically or enzymatically cleavable under physiologicalconditions,

as well as their physiologically acceptable salts and theirstereoisomers, enantiomers or diastereomers in optically pure form.

Deuterated catecholamine derivatives, according to the invention arepreferred, wherein the difference between the deuterium enrichment of R₂and R₃ is at least 7 percentage points.

Deuterated catecholamine derivatives, according to the invention arepreferred, wherein the difference between the deuterium enrichment of R₂and R₃ is at least 10 percentage points.

Deuterated catecholamine derivatives, according to the invention arepreferred, wherein the difference between the deuterium enrichment of R₂and R₃ is at least 15 percentage points.

Deuterated catecholamine derivatives, according to the invention arepreferred, wherein the difference between the deuterium enrichment of R₂and R₃ is at least 20 percentage points.

Deuterated catecholamine derivatives, according to the invention arepreferred, wherein R₄ is selected from the group comprising hydrogen,deuterium, methyl, perdeuteromethyl, ethyl, perdeuteroethyl, propyl,perdeuteropropyl, butyl, perdeuterobutyl, C₁ to C₆-alkyl, that may bebranched or unbranched, or C₅ to C₆-cycloalkyl, deuterated or partlydeuterated C₁ to C₆-alkyl, that may be branched or unbranched, ordeuterated or partly deuterated C₅ to C₆-cycloalkyl.

Deuterated catecholamine derivatives, according to the invention arepreferred, wherein R₄ is selected from the group comprising hydrogen,deuterium, methyl, perdeuteromethyl, ethyl, perdeuteroethyl, propyl,perdeuteropropyl, cyclohexyl, and perdeuterocyclohexyl.

Deuterated catecholamine derivatives, according to the invention arepreferred, wherein R₄ is hydrogen.

Deuterated catecholamine derivatives, according to the invention arepreferred, wherein R₄ is methyl.

Deuterated catecholamine derivatives, according to the invention arepreferred, wherein R₄ is ethyl.

Especially preferred according to the present invention isL-2-amino-2,3,3*-trideutero-3-(3,4-dihydroxyphenyl) propionic acid(α,β,β*-D3-L-DOPA), wherein 3* indicates that the deuterium enrichmentin one β-position is about 90 mol %. This compound has according to thedefinition of the present invention a difference in the deuteriumenrichment in the β-positions of about 8 to 10 percentage points. Theother positions carrying deuterium are completely deuterated and show adeuterium enrichment of at least 98 mol %. This compound is named TestItem D in Tables 1 and 2 as outlined in the present description herein.

The problem is also solved by providing deuterated catecholaminederivatives, obtainable by admixing a compound of general Formula II

with a compound of general Formula III or general Formula IV

wherein, in general Formula II, III, or IV,

R₄ is hydrogen, deuterium, C₁ to C₆-alkyl or C₅ to C₆-cycloalkyl,deuterated C₁ to C₆-alkyl or C₅ to C₆-cycloalkyl, or a group that iseasily hydrolytically or enzymatically cleavable under physiologicalconditions,

as well as their physiologically acceptable salts and theirstereoisomers, enantiomers or diastereomers in optically pure form,

in a ratio to adjust the deuterium enrichment in position R₂ or R₃ ingeneral Formula I within the predefined range of 0.02 mol % to 100 mol %deuterium.

Preferred are, according to the present invention, deuteratedcatecholamine derivatives, wherein the compound according to generalFormula II is selected from the list comprising

-   L-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl) propionic acid,-   L-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl) methyl    propionate,-   L-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl) ethyl propionate,-   L-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl) propyl    propionate,-   L-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl) cyclohexyl    propionate,-   L-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl) perdeuteromethyl    propionate,-   L-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl) perdeuteroethyl    propionate,-   L-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl)    perdeuteropropylethyl propionate,-   L-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl)    perdeuterocyclohexyl propionate,

as well as their physiologically acceptable salts and theirstereoisomers, enantiomers or diastereomers in optically pure form,

and wherein the compound according to general Formula III or generalFormula IV is selected from the list comprising

-   L-2-amino-2,3-dideutero-3-(3,4-dihydroxyphenyl) propionic acid,-   L-2-amino-2,3-dideutero-3-(3,4-dihydroxyphenyl) methyl propionate,-   L-2-amino-2,3-dideutero-3-(3,4-dihydroxyphenyl) ethyl propionate,-   L-2-amino-2,3-dideutero-3-(3,4-dihydroxyphenyl) propyl propionate,-   L-2-amino-2,3-dideutero-3-(3,4-dihydroxyphenyl) cyclohexyl    propionate,-   L-2-amino-2,3-dideutero-3-(3,4-dihydroxyphenyl) perdeuteromethyl    propionate,-   L-2-amino-2,3-dideutero-3-(3,4-dihydroxyphenyl) perdeuteroethyl    propionate,-   L-2-amino-2,3-dideutero-3-(3,4-dihydroxyphenyl)    perdeuteropropylethyl propionate,-   L-2-amino-2,3-dideutero-3-(3,4-dihydroxyphenyl) perdeuterocyclohexyl    propionate,

as well as their physiologically acceptable salts and theirstereoisomers, enantiomers or diastereomers in optically pure form.

Especially preferred are deuterated catecholamine derivatives, whereinthe percentage of the compound according to general Formula II is in therange of 0.1 mol % to 99.9 mol %, preferably in the range of 5 mol % to95 mol %, especially preferred in the range of 78 mol % to 95 mol %.Most preferred are herein deuterated catecholamine derivatives, whereinthe percentage of the compound according to general Formula II is in therange of 88 mol % to 92 mol %. Most preferred are herein also deuteratedcatecholamine derivatives, wherein the percentage of the compoundaccording to general Formula II is in the range of 78 mol % to 82 mol %.

Therefore, according to the invention a mixture is preferred in which 90mol % of L-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl) propionicacid are admixed with 10 mol % ofL-2-amino-2,3-dideutero-3-(3,4-dihydroxyphenyl) propionic acid, or inwhich 80 mol % of L-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl)propionic acid are admixed with 20 mol % ofL-2-amino-2,3-dideutero-3-(3,4-dihydroxyphenyl) propionic acid, or inwhich 85 mol % of L-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl)propionic acid are admixed with 15 mol % ofL-2-amino-2,3-dideutero-3-(3,4-dihydroxyphenyl) propionic acid, or inwhich 70 mol % of L-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl)propionic acid are admixed with 30 mol % ofL-2-amino-2,3-dideutero-3-(3,4-dihydroxyphenyl) propionic acid.

A further object of the present invention is a method for thepreparation of deuterated catecholamine derivatives according to thepresent invention, by mixing

(i) a compound according to general Formula I:

wherein

R₁, R₂, R₃, and R₄ have the meaning as given above,

as well as their physiologically acceptable salts and theirstereoisomers, enantiomers or diastereomers in optically pure form,

wherein the deuterium enrichment of R₂ and R₃ is different from eachother and that the difference between the deuterium enrichment of R₂ andR₃ has a first predefined value

with (ii) at least one compound according to general Formula I:

wherein

R₁, R₂, R₃, and R₄ have the meaning as above,

as well as their physiologically acceptable salts and theirstereoisomers, enantiomers or diastereomers in optically pure form,

wherein the deuterium enrichment of R₂ and R₃ is different from eachother and that the difference between the deuterium enrichment of R₂ andR₃ has a second predefined value,

(iii) in a ratio that yields a predefined difference between thedeuterium enrichment of R₂ and R₃, which is in the range from at least 5to at least 20 percentage points.

A further object of the present invention is the use of the deuteratedcatecholamine derivatives according to the invention as well asphysiologically acceptable salts thereof, for the treatment of dopaminedeficiency diseases or diseases which are based on disrupted tyrosinetransport or disrupted tyrosine decarboxylase, such as Parkinson'sdisease, restless leg syndrome, dystonia, for inhibiting prolactinsecretion, for stimulating the release of growth hormone, for thetreatment of neurological symptoms of chronic manganese intoxications,of amyotrophic lateral sclerosis and of multiple system atrophy.

Preferred is the use of the deuterated catecholamine derivativesaccording to the invention as well as physiologically acceptable saltsthereof, in combination with an enzyme inhibitor or several enzymeinhibitors, for the treatment of dopamine deficiency diseases ordiseases which are based on disrupted tyrosine transport or disruptedtyrosine decarboxylase, such as Parkinson's disease, restless legsyndrome, dystonia, for inhibiting prolactin secretion, for stimulatingthe release of growth hormone, for the treatment of neurologicalsymptoms of chronic manganese intoxications, of amyotrophic lateralsclerosis and of multiple system atrophy.

Preferred is the use of the deuterated catecholamine derivativesaccording to the invention as well as physiologically acceptable saltsthereof, further characterized in that the enzyme inhibitor or theenzyme inhibitors involve decarboxylase inhibitors and/orcatechol-O-methyltransferase inhibitors and/or monoamine oxidaseinhibitors and/or ß-hydroxylase inhibitors.

Preferred is the use of the deuterated catecholamine derivativesaccording to the invention as well as physiologically acceptable saltsthereof, further characterized in that the decarboxylase inhibitor isselected from the group consisting ofD,L-serine-2-(2,3,4-trihydroxybenzyl) hydrazide (benserazide),(+L-α-hydrazino-3,4-dihydroxy-α-methylhydrocinnamic acid (carbidopa),L-serine-2-(2,3,4-trihydroxybenzyl) hydrazide,glycine-2-(2,3,4-trihydroxybenzyl) hydrazide andL-tyrosine-2-(2,3,4-trihydroxybenzyl) hydrazide as well asphysiologically acceptable salts thereof.

Preferred is the use of the deuterated catecholamine derivativesaccording to the invention as well as physiologically acceptable saltsthereof further characterized in that the catechol-O-methyltransferaseinhibitor is selected from entacapone and cabergoline as well asphysiologically acceptable salts thereof.

Preferred is the use of the deuterated catecholamine derivativesaccording to the invention as well as physiologically acceptable saltsthereof, further characterized in that the monoamine oxidase inhibitoris selected from the group consisting of selegiline, moclobemide andtranylcypromine as well as physiologically acceptable salts thereof.

Preferred is the use of the deuterated catecholamine derivativesaccording to the invention as well as physiologically acceptable saltsthereof, further characterized in that the ß-hydroxylase inhibitor isselected from calcium 5-butyl picolinate and calcium 5-pentyl picolinateas well as physiologically acceptable salts thereof.

Preferred is the use of the deuterated catecholamine derivativesaccording to the invention as well as physiologically acceptable saltsthereof, for the production of pharmaceuticals for the treatment ofParkinson's disease, restless leg syndrome, of amyotrophic lateralsclerosis and of multiple system atrophy.

A further object of the present invention is a pharmaceuticalcomposition, which contains deuterated catecholamines according to theinvention as well as physiologically acceptable salts thereof, for thetreatment of Parkinson's disease, of restless leg syndrome, of dystonia,for inhibiting prolactin secretion, for stimulating the release ofgrowth hormone, for the treatment of neurological symptoms of chronicmanganese intoxications, of amyotrophic lateral sclerosis and ofmultiple system atrophy, in addition to pharmaceutically acceptableadjuvants and additives.

Preferred is a pharmaceutical composition, which comprises deuteratedcatecholamines according to the invention as well as physiologicallyacceptable salts thereof, for the treatment of Parkinson's disease,restless leg syndrome, dystonia, for inhibiting prolactin secretion, forstimulating the release of growth hormone, for the treatment ofneurological symptoms of chronic manganese intoxications, of amyotrophiclateral sclerosis and of multiple system atrophy, as well as one or moreenzyme inhibitors, in addition to pharmaceutically acceptable adjuvantsand additives.

Preferred is a pharmaceutical composition, which comprises deuteratedcatecholamines according to the invention, further characterized in thatthe enzyme inhibitor or the enzyme inhibitors involve decarboxylaseinhibitors and/or catechol-O-methyltransferase inhibitors and/ormonoamine oxidase inhibitors and/or ß-hydroxylase inhibitors.

Preferred is a pharmaceutical composition, which comprises deuteratedcatecholamines according to the invention, further characterized in thatthe decarboxylase inhibitor is selected from the group consisting ofD,L-serine-2-(2,3,4-trihydroxybenzyl) hydrazide (benserazide),(−)-L-α-hydrazino-3,4-dihydroxy-α-methylhydrocinnamic acid (carbidopa),L-serine-2-(2,3,4-trihydroxybenzyl) hydrazide,glycine-2-(2,3,4-trihydroxybenzyl) hydrazide andL-tyrosine-2-(2,3,4-trihydroxybenzyl) hydrazide as well asphysiologically acceptable salts thereof.

Preferred is a pharmaceutical composition, which comprises deuteratedcatecholamines according to the invention, further characterized in thatthe catechol-O-methyltransferase inhibitor is selected from entacaponeand cabergoline as well as physiologically acceptable salts thereof.

Preferred is a pharmaceutical composition, which comprises deuteratedcatecholamines according to the invention, further characterized in thatthe monoamine oxidase inhibitor is selected from the group consisting ofselegiline, moclobemide and tranylcypromine as well as physiologicallyacceptable salts thereof.

Preferred is a pharmaceutical composition, which comprises deuteratedcatecholamines according to the invention, further characterized in thatthe ß-hydroxylase inhibitor is selected from calcium 5-butyl picolinateand calcium 5-pentyl picolinate as well as physiologically acceptablesalts thereof.

Still another object of the present invention is a pharmaceuticalcomposition, which comprises a mixture of 10 mol % ofL-2-amino-2,3-dideutero-3-(3,4-dihydroxyphenyl) propionic acid as wellas physiologically acceptable salts thereof, and 90 mol % ofL-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl) propionic acid aswell as physiologically acceptable salts thereof, in a pharmacologicallyactive amount, optionally in addition with pharmaceutically acceptableadjuvants and additives.

Preferred is a pharmaceutical composition, wherein the compositionfurther comprises, in a pharmacologically active amount, carbidopa,benserazide or entacapone or a mixture of the said compounds.

The pharmaceutical compositions of the present invention are verypowerful in the treatment of Parkinson's disease as the asymmetricposition specific deuterium enrichment can tune the known effects ofposition specific deuterated L-DOPA. This provides a powerful tool toadjust the treatment according to the symptoms and side effects thatchange during disease progression.

According to the stage of Parkinson's disease in the respective person,one can use a compounds with a deuterium enrichment adjusted to the needof the patient under treatment. This offers new opportunities for amedication that is tailor-made or customized to the patient.

Another object of the present invention is a method for the treatment ofdopamine deficiency diseases or diseases which are based on disruptedtyrosine transport or disrupted tyrosine decarboxylase, such asParkinson's disease, restless leg syndrome, dystonia, for inhibitingprolactin secretion, for stimulating the release of growth hormone, forthe treatment of neurological symptoms of chronic manganeseintoxications, of amyotrophic lateral sclerosis and of multiple systematrophy with a person who has been identified as a person who is in theneed of the treatment of dopamine deficiency diseases or diseases whichare based on disrupted tyrosine transport or disrupted tyrosinedecarboxylase, such as Parkinson's disease, restless leg syndrome,dystonia, for inhibiting prolactin secretion, for stimulating therelease of growth hormone, for the treatment of neurological symptoms ofchronic manganese intoxications, of amyotrophic lateral sclerosis and ofmultiple system atrophy, the method comprising administering to theperson deuterated catecholamine derivatives according to the inventionas given in general formula as well as physiologically acceptable saltsthereof.

Preferred is the method, wherein the administering to the person is incombination with an enzyme inhibitor or several enzyme inhibitors.

Preferred is the method, wherein the enzyme inhibitor or the enzymeinhibitors involve decarboxylase inhibitors and/orcatechol-O-methyltransferase inhibitors and/or monoamine oxidaseinhibitors and/or ß-hydroxylase inhibitors.

Preferred is the method, wherein the decarboxylase inhibitor is selectedfrom the group consisting of D,L-serine-2-(2,3,4-trihydroxybenzyl)hydrazide (benserazide),(+L-α-hydrazino-3,4-dihydroxy-α-methylhydrocinnamic acid (carbidopa),L-serine-2-(2,3,4-trihydroxybenzyl)hydrazide,glycine-2-(2,3,4-trihydroxybenzyl)hydrazide andL-tyrosine-2-(2,3,4-trihydroxybenzyl)hydrazide as well asphysiologically acceptable salts thereof.

Preferred is the method, wherein the catechol-O-methyltransferaseinhibitor is selected from entacapone and cabergoline as well asphysiologically acceptable salts thereof.

Preferred is the method, wherein the monoamine oxidase inhibitor isselected from the group consisting of selegiline, moclobemide andtranylcypromine as well as physiologically acceptable salts thereof.

Preferred is the method, wherein the ß-hydroxylase inhibitor is selectedfrom calcium 5-butyl picolinate and calcium 5-pentyl picolinate as wellas physiologically acceptable salts thereof.

The preparation of the deuterated catecholamine derivatives of thepresent invention can be performed in at least two principal ways. Oneway is to mix compounds with a certain deuterium enrichment withcompounds which have only hydrogen or only a highly enriched (>98% D)deuterium substitution at a certain position. By mixing at least twocompounds any required enrichment level of deuterium at any position canbe obtained. The other way of preparation is to add specificallyenriched starting material to a certain step during the preparationprocess of the compounds according to the invention.

The preparation of deuterium enriched catecholamine derivatives is knownfrom WO-A 2004/056724 and WO-A 2007/093450. In there, the preparation ofselectively deuterated DOPA derivatives is disclosed that have adeuterium enrichment in the respective position within the molecule ofat least 98%.

One preferred synthetic pathway is shown in Scheme 1.

According to the present invention it is preferred to prepare thecompounds according to the invention by adding non-deuterated educts 3aand/or 4 and/or 5 to the respective deuterated compounds. The ratio ofdeuterated and non-deuterated compounds is adjusted in such a manner toobtain the desired ratio in the end product. This method of productionhas the advantage that no further mixing steps are required. Thisobtained product is then by definition no longer a mixture.

For the production of the physiologically acceptable salts of thedeuterated catecholamine derivatives according to the invention, theusual physiologically acceptable inorganic and organic acids such ashydrochloric acid, hydrobromic acid, phosphoric acid, sulfuric acid,oxalic acid, maleic acid, fumaric acid, lactic acid, tartaric acid,malic acid, citric acid, salicylic acid, adipic acid and benzoic acidcan be used. Additional acids that can be used are described, forexample, in Fortschritte der Arzneimittelforschung, Vol. 10, pp.224-225, Birkhäuser Publishers, Basel and Stuttgart, 1966, and Journalof Pharmaceutical Sciences, Vol. 66, pp. 1-5 (1977).

The acid addition salts are usually obtained in a way known in and ofitself by mixing the free base or solutions thereof with thecorresponding acid or solutions thereof in an organic solvent, forexample, a lower alcohol, such as methanol, ethanol, n-propanol orisopropanol or a lower ketone such as acetone, methyl ethyl ketone ormethyl isobutyl ketone or an ether such as diethyl ether,tetrahydrofuran or dioxane. For better crystal precipitation, mixturesof the named solvents can also be used. In addition, physiologicallyacceptable aqueous solutions of acid addition salts of the compoundsused according to the invention can be produced therefrom in an aqueousacid solution.

The acid addition salts of the compounds according to the invention canbe converted to the free base in a way known in and of itself, e.g.,with alkali or ion exchangers. Additional salts can be obtained from thefree base by reaction with inorganic or organic acids, particularlythose which are suitable for the formation of salts that can be employedtherapeutically. These or also other salts of the compound according tothe invention, such as, e.g., the picrate, may also serve forpurification of the free base by converting the free base into a salt,separating this salt, and afterwards releasing the base from the salt.

The subject of the present invention is also pharmaceuticals for oral,buccal, sublingual, nasal, rectal, subcutaneous, intravenous orintramuscular application as well as for inhalation, which, in additionto the usual vehicle and dilution agents, also contain a compound ofgeneral Formula I or the acid addition salt thereof as an activeingredient.

The pharmaceuticals of the invention are produced, in the known way andwith suitable dosage, with the usual solid or liquid vehicle substancesor dilution agents and the commonly used pharmaceutical-technicaladjuvants corresponding to the desired type of application. Thepreferred preparations consist of a form for administration which issuitable for oral application. Such forms of administration include, forexample, tablets, sucking tablets, film tablets, dragees, capsules,pills, powders, solutions, aerosols or suspensions or slow-releaseforms.

Of course, parenteral preparations such as injection solutions are alsoconsidered. In addition, suppositories, for example, have also beennamed as preparations. Corresponding tablets can be obtained, forexample, by mixing the active substance with known adjuvants, forexample, inert dilution agents such as dextrose, sugar, sorbitol,mannitol, polyvinylpyrrolidone, bursting agents such as corn starch oralginic acid, binders such as starches or gelantins, lubricants such asmagnesium stearate or talc and/or agents for achieving a slow-releaseeffect such as carboxypolymethylene, carboxymethylcellulose, celluloseacetate phthalate or polyvinyl acetate. The tablets may also consist ofseveral layers.

Dragees can also be produced correspondingly, for controlled or delayedrelease forms of preparation, by coating the cores produced analogouslyto the tablets with agents commonly used in dragee coatings, forexample, polyvinylpyrrolidone or shellac, gum arabic, talc, titaniumdioxide or sugar. The dragee envelope may also consist of severallayers, wherein the adjuvants mentioned above in the case of tablets canbe used.

Solutions or suspensions containing the active substance used accordingto the invention may additionally contain agents that improve taste,such as saccharin, cyclamate or sugar, as well as, e.g., taste enhancerssuch as vanilla or orange extract. They may also contain suspensionadjuvants such as sodium carboxymethylcellulose or preservatives such asp-hydroxybenzoate. Capsules containing active substances can beproduced, for example, by mixing the active substance with an inertvehicle such as lactose or sorbitol and encapsulating this mixture ingelatin capsules. Suitable suppositories can be produced, for example,by mixing with vehicle agents provided therefore, such as neutral fatsor polyethylene glycol or derivatives thereof.

The production of the pharmaceutical preparations according to theinvention is known in the art, and is described in handbooks known tothe person skilled in the art, for example, Hager's Handbuch [Handbook](5th ed.) 2, 622-1045; List et al., Arzneiformenlehre [Instructions forDrug Forms], Stuttgart: Wiss. Verlagsges. 1985; Sucker et al.,Pharmazeutische Technologie [Pharmaceutical Technology], Stuttgart:Thieme 1991; Ullmann's Enzyklopadie [Encyclopedia] (5th ed.) A 19,241-271; Voigt, Pharmazeutische Technologie [Pharmaceutical Technology],Berlin: Ullstein Mosby 1995.

The following examples shall explain the present invention. The examplesshall be understood only as a preferred embodiment of the invention. Itis not intended to limit the present invention to the scope of the givenexamples.

EXAMPLE 1

The effects on motor performance and the development of dyskinesiafollowing administration of deuterated L-DOPA derivatives with differentdeuterium enrichment at specific position of the side chain have beencompared among each other and to L-DOPA in the 6-hydroxydopamine(6-OHDA) rodent model of Parkinson's disease. The tested compounds andthe specific deuterium enrichment of these compounds are displayed inTable 1.

TABLE 1 Test Items Deuterium Enrichment Name α β_(R) β_(S) AL-2-amino-3-(3,4-dihydroxyphenyl) NA NA NA propionic acid (L-DOPA) BS/S-2-amino-2,3-dideutero-3- >98% <1% >98% (3,4-dihydroxyphenyl)propionic acid (α,β-D2-L-DOPA) CL-2-amino-2,3,3-trideutero-3- >98% >98%  >98% (3,4-dihydroxyphenyl)propionic acid (α,β,β-D3-D3-L-DOPA) DL-2-amino-2,3,3*-trideutero-3- >98% 90% >98% (3,4-dihydroxyphenyl)propionic acid (α,β,β*-D3-L-DOPA) (3* or β*, respectively, indicatesthat the position is not completely deuterated) (β_(R) and β_(S) relateto the commonly used R/S nomenclature indicating the relative positionsin optically active compounds)

Female Sprague-Dawley rats weighing approximately 225 g were housed on a12-hour light/dark cycle and kept on standard laboratory diet and waterad libitum. The rats were lesioned by unilateral injection of theneurotoxin 6-OHDA. The lesion was validated by measuring the rotationalactivity after i.p. injection of 2.5 mg/kg D-amphetamine.

The anti-Parkinson effect (effect on motor performance) was evaluated bymeasurement of drug induced contralateral rotations. A dose effect wasestablished to determine the equipotent (equi-effective) dose.

Dyskinesia was evaluated after repeated treatment by scoring the animalsfor abnormal involuntary movements. The rats were scored, by an observerblinded to the experimental design for limb, axial and orolingualinvoluntary movements.

The equipotent dose as percent of L-DOPA dose that caused the sameeffect on motor performance and dyskinesia observed following repeatedadministration of these doses is shown in Table 2.

TABLE 2 Results Equipotent Dose Motor Effect Dyskinesia [% of [% of [%of L-DOPA L-DOPA dyskinesia caused Test Item dose] effect] by L-DOPA] A100%  100% 100% B 30% 100% 100% C 60% 100%  50% D 35% 100%  50%

The effect of α,β-D2-L-DOPA [B] on motor performance is significantlygreater compared to α,β,β-D3-L-DOPA [C] and L-DOPA [A] as reflected by alower equipotent dose. However dyskinesia after α,β-D2-L-DOPA [B] is notreduced in comparison to L-DOPA at equipotent dose whereasα,β,β-D3-L-DOPA [C] caused significantly less dyskinesia than L-DOPA atequipotent dose.

Surprisingly, test item D with almost 100% deuterium enrichment inposition α and βs and 90% in position β_(R) provides both a motor effectequivalent to the di-deuterated α,β-D2-L-DOPA [B] and a reduction ofdyskinesia as the triple-deuterated α,β,β-D3-L-DOPA [C].

Test compound D is thus the optimal treatment for late stage Parkinsonpatients suffering from motor fluctuations and LIDs and requiring highdoses of L-DOPA.

The example of compound D shows that asymmetric position specificdeuterium enrichment can tune the known effects of position specificdeuterated L-DOPA. This provides a powerful tool to adjust the treatmentaccording to the symptoms and side effects that change during diseaseprogression.

According to the stage of Parkinson's disease in the respective person,one can use a compounds with a deuterium enrichment adjusted to the needof the patient under treatment. This offers new opportunities for amedication that is tailor-made or customized to the patient.

EXAMPLE 2 Preparation of Test Compound D from Table 1L-2-Amino-2,3,3*-trideutero-3-(3,4-dihydroxyphenyl) propionic acid(α,β,β*-D3-L-DOPA)

Test item D has a deuterium enrichment of 90% in β_(R) position.

D is obtained by mixing 10 mol %L-2-amino-2,3(S)-dideutero-3-(3,4-dihydroxyphenyl) propionic acid with90 mol % L-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl) propionicacid (deuterium enrichment >98% in all three positions). Experimentaldata for C₉H_(8.1) ²H_(2.9)NO₄

Calculated: H 6.95 C 54.05 N 7.00 O 32.00 Analyt.: H 7.00 C 54.02 N 7.00O 31.98

The degree of deuteration has also been determined by NMR spectroscopy.For that purpose NMR spectra with a 500 MHz spectrometer have beenrecorded. As a solvent, d₆-DMSO was used. The following Table 3 showsthe respective position within the compound of test item D and theintegral (AUC=area under curve) of the registered spectra, reflectingthe content of hydrogen at the respective positions.

TABLE 3 NMR results Position Integral (AUC) Ring 3.02 α 0.02 β 0.01 β*0.10

The preparation of the starting materialL-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl) propionic acid isdescribed in WO-A 2004/056724, the preparation of the starting materialL-2-Amino-2,3(S)-dideutero-3-(3,4-dihydroxyphenyl) propionic acid isdescribed in WO-A 2007/093450.

After mixing the compounds the mixture may be processed further in orderto obtain a suitable pharmaceutical product for the medication ofParkinson's disease as given in the following examples.

EXAMPLE 3

Tablet with Film Coating Containing α,β,β*-D3-L-DOPA

Composition of the core: α,β,β*-D3-L-DOPA (Test Item D) 40.00 mgPovidone 20.00 mg Sorbitol 7.00 mg Silicon dioxide, highly dispersed 2mg Pregelatinated starch 40.00 mg Croscarmellose-sodium 13.30 mgCarmellose-sodium 20.05 mg Microcrystalline cellulose 41.00 mg Magnesiumstearate 2.00 mg Film coating: Hydroxypropylmethylcellulose 16.00 mgMacrogol 400 ™ 2.50 mg Titanium oxide 3.00 mg Talc 3.00 mg

Preparation:

α,β,β*-D3-L-DOPA (Test Item D) and highly dispersed silicon dioxide aregranulated in a compulsory mixer with a solution of povidone andsorbitol. The granules are dried, screened, mixed with pregelatinatedstarch, croscarmellose sodium, carmellose sodium and microcrystallinecellulose, then combined with magnesium stearate and compressed intotablets. The tablets are film coated with hydroxypropylmethylcellulose,Macrogol, titanium dioxide and talc.

EXAMPLE 4

Tablet with Film Coating Containing α,β,β*-D3-L-DOPA and Carbidopa

Composition of the core: α,β,β*-D3-L-DOPA (Test Item D) 35.00 mgCarbidopa 25.00 mg Povidone 20.00 mg Sorbitol 7.00 mg Silicon dioxide,highly dispersed 2 mg Pregelatinated starch 40.00 mgCroscarmellose-sodium 13.30 mg Carmellose-sodium 20.05 mgMicrocrystalline cellulose 41.00 mg Magnesium stearate 2.00 mg Filmcoating: Hydroxypropylmethylcellulose 16.00 mg Macrogol 400 ™ 2.50 mgTitanium oxide 3.00 mg Talc 3.00 mg

Preparation:

α,β,β*-D3-L-DOPA (Test Item D), carbidopa and highly dispersed silicondioxide are granulated in a compulsory mixer with a solution of povidoneand sorbitol. The granules are dried, screened, mixed withpregelatinated starch, croscarmellose sodium, carmellose sodium andmicrocrystalline cellulose, then combined with magnesium stearate andcompressed into tablets. The tablets are film coated withhydroxypropylmethylcellulose, Macrogol, titanium dioxide and talc.

EXAMPLE 5

Tablet with Film Coating Containing Microencapsulated α,β,β*-D3-L-DOPAand Carbidopa

Composition of the core: α,β,β*-D3-L-DOPA (Test Item D) 40.00 mgCarbidopa 25.00 mg Tartaric acid 5.00 mg Povidone 20.00 mg Sorbitol 7.00mg Eudragit RL ™ solid 20.00 mg Silicon dioxide, highly dispersed 2 mgPregelatinated starch 40.00 mg Croscarmellose-sodium 13.30 mgCarmellose-sodium 20.05 mg Microcrystalline cellulose 41.00 mg Magnesiumstearate 2.00 mg Film coating: Hydroxypropylmethylcellulose 16.00 mgMacrogol 400 ™ 2.50 mg Titanium oxide 3.00 mg Talc 3.00 mg

Preparation:

α,β,β*-D3-L-DOPA (Test Item D), Carbidopa, sorbitol and Eudragit aremicroencapsulated and homogenised in a barrel mixer with tartaric acid,highly dispersed silicon dioxide, povidone, pregelatinated starch,croscarmellose sodium, carmellose sodium and microcrystalline cellulose,then combined with magnesium stearate and compressed into tablets. Thetablets are film coated with hydroxypropylmethylcellulose, Macrogol,titanium dioxide and talc.

EXAMPLE 6

Tablet with Film Coating Containing Microencapsulated α,β,β*-D3-L-DOPAand Benserazide

Composition of the core: α,β,β*-D3-L-DOPA (Test Item D) 40.00 mgBenserazide 25.00 mg Tartaric acid 5.00 mg Povidone 20.00 mg Sorbitol7.00 mg Eudragit RLTM solid 20.00 mg Silicon dioxide, highly dispersed 2mg Pregelatinated starch 40.00 mg Croscarmellose-sodium 13.30 mgCarmellose-sodium 20.05 mg Microcrystalline cellulose 41.00 mg Magnesiumstearate 2.00 mg Film coating: Hydroxypropylmethylcellulose 16.00 mgMacrogol 400 ™ 2.50 mg Titanium oxide 3.00 mg Talc 3.00 mg

The preparation of the film coated tablets is as given in Example 5.

EXAMPLE 7

Tablet with Film Coating Containing α,β,β*-D3-L-DOPA and Benserazide

Composition of the core: α,β,β*-D3-L-DOPA (Test Item D) 35.00 mgBenserazide 25.00 mg Povidone 20.00 mg Sorbitol 7.00 mg Silicon dioxide,highly dispersed 2 mg Pregelatinated starch 40.00 mgCroscarmellose-sodium 13.30 mg Carmellose-sodium 20.05 mgMicrocrystalline cellulose 41.00 mg Magnesium stearate 2.00 mg Filmcoating: Hydroxypropylmethylcellulose 16.00 mg Macrogol 400 ™ 2.50 mgTitanium oxide 3.00 mg Talc 3.00 mg

Preparation:

α,β,β*-D3-L-DOPA (Test Item D), carbidopa, and highly dispersed silicondioxide are granulated in a compulsory mixer with a solution of povidoneand sorbitol. The granules are dried, screened, mixed withpregelatinated starch, croscarmellose sodium, carmellose sodium andmicrocrystalline cellulose, then combined with magnesium stearate andcompressed into tablets. The tablets are film coated withhydroxypropylmethylcellulose, Macrogol, titanium dioxide and talc.

EXAMPLE 8

Tablet with Film Coating Containing α,β,β*-D3-L-DOPA and Carbidopa andEntacapone

Composition of the core: α,β,β*-D3-L-DOPA (Test Item D) 40.00 mgCarbidopa 25.00 mg Entacapone 200.00 mg Povidon K30 20.00 mgCrospovidone Type B 15.00 mg Mannitol 9.00 mg Silicon dioxide, highlydispersed 2 mg Pregelatinated starch 40.00 mg Croscarmellose-sodium13.30 mg Carmellose-sodium 20.05 mg Microcrystalline cellulose 41.00 mgMagnesium stearate 2.00 mg Film coating: Hydroxypropylmethylcellulose16.00 mg Macrogol 400 ™ 2.50 mg Titanium oxide 3.00 mg Talc 3.00 mg

The preparation of the film coated tablet is performed as described inExample 3.

What is claimed:
 1. A pharmaceutical composition comprisingL-2-amino-2,3,3-trideutero-3-(3,4-dihydroxyphenyl) propionic acid, or aphysiologically acceptable salt thereof, having a deuterium enrichmentabove the natural abundance of deuterium; andL-2-amino-2,3-dideutero-3-(3,4-dihydroxyphenyl) propionic acid, or aphysiologically acceptable salt thereof, having a deuterium enrichmentabove the natural abundance of deuterium.